A compressor includes first and second scroll members, a structure supporting the second scroll member, and a first piston. The first scroll member includes a first end plate and a first spiral wrap. The second scroll member includes a second end plate and a second spiral wrap engaged with the first spiral wrap to form compression pockets. The second end plate includes a first aperture in communication with a first compression pocket. The structure includes a first recess and first and second passages. The first piston is axially displaceable between first and second positions within the first recess. The first piston isolates the first passage from communication with the second passage when in the first and second positions, prevents communication between the first aperture and the first passage when in the first position, and provides communication between the first aperture and the first passage when in the second position.